Clear poly repair

[Paul Chick (EarthLink)]

----- Original Message -----
From: "Ron Overs" <sec@overspianos.com.au>
To: <pmc333@earthlink.net>; "Pianotech" <pianotech@ptg.org>
Sent: Friday, January 03, 2003 3:13 AM
Subject: RE: Clear poly repair

 We use a 2 pack polyurethane sealer to isolate the
 coloured veneer from the bleaching characteristics of the MEKP. It
 still takes some experience to get the colour right, since the poly
 layer will tend to collect light onto the coloured area. The repaired
 area must look a few shades darker relative to the surrounding
 undamaged area if the colour is to look right once the poly is poured.

 One technique I use, when developing the appropriate stain colour for
 the repair, is to spray the stain onto a strip of polycarbonate film.
 This strip can be held over the repair to make an assessment of the
 tone colour prior to applying it to the veneer repair. This can save
 a lot of time washing off inappropriate stains to start over.

 Ron O.

Ron
Are the properties of the 2 part polyurethane sealer much different than
polyurethane topcoat?  Will polyester adhere to both equally well?

Clever idea using the polycarbonate film.

 I have had test repairs come out a little lighter under the poly, and I
learned that the amount of hardener mixed with clear poly will affect the
amber tint, that is, the more hardener added the more amber the clear poly
gets. Small batches make it harder to control this tinting from the chemical
reaction. I have thought about using clear gloss polyurethane instead of
clear poly as the topcoat if the damaged area gets little or no wear, but it
may wear differently on edge of a lid or "age" to a different hue and be too
noticable.  Have you tried this?

Thanks for your time answering these questions.

Paul Chick